A018232 - OEIS

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A018232

Consider pairs (k,m) such that k^2 begins with a 1 and when the 1 is changed to a 2 we again get a square, m^2; sequence gives values of m for primitive solutions.

145, 4625, 17225, 454625, 14753125, 53948125, 1425503125, 47063515625, 168971890625, 150145486328125, 529265958203125, 479035044775390625, 1657888279384765625, 1528441794923095703125, 5193483785077392578125, 4877043905134674072265625

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OFFSET

1,1

COMMENTS

Primitive here means that if (k,m) is a solution, solutions like (10^t*k,10^t*m) are ignored. - Sean A. Irvine, Feb 05 2019

REFERENCES

Posting by Noam D. Elkies to netnews circa Oct 15 1992.

LINKS

Sean A. Irvine, Table of n, a(n) for n = 1..40

Noam D. Elkies, Cliff Puzzle 8: Squares and Squares and Squares, rec.puzzles Archive (pickover), part 29 of 35, 17 Aug 1993.

CROSSREFS

Cf. A018233.